perf: lazy-load cli startup modules

[vincentkoc]

Summary

• lazy-load session, output, queue, and skillflag modules from cli-core instead of importing them eagerly at startup
• add an early --version fast path before config and command graph setup
• keep the change scoped to CLI startup so one-shot commands pay less module parse/load work

Notes

• the build now code-splits the lazily imported session/output/queue code from dist/cli.js
• spot checks after pnpm run build showed node dist/cli.js --version averaging about 180ms over warm runs in this worktree

Testing

• pnpm exec tsc -p tsconfig.json --noEmit
• pnpm test